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Yang, Xiaoming, Taiqiang Cao, Xiaohua Zhang, Tianqian Li, and Hang Luo. "Numerical Investigation of Transient Breakdown Voltage Enhancement in SOI LDMOS by Using a Step P-Type Doping Buried Layer." Micromachines 14, no. 4 (April 20, 2023): 887. http://dx.doi.org/10.3390/mi14040887.
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In this paper, the transient breakdown voltage (TrBV) of a silicon-on-insulator (SOI) laterally diffused metal-oxide-semiconductor (LDMOS) device was increased by introducing a step P-type doping buried layer (SPBL) below the buried oxide (BOX). Device simulation software MEDICI 0.13.2 was used to investigate the electrical characteristics of the new devices. When the device was turned off, the SPBL could enhance the reduced surface field (RESURF) effect and modulate the lateral electric field in the drift region to ensure that the surface electric field was evenly distributed, thus increasing the lateral breakdown voltage (BVlat). The enhancement of the RESURF effect while maintaining a high doping concentration in the drift region (Nd) in the SPBL SOI LDMOS resulted in a reduction in the substrate doping concentration (Psub) and an expansion of the substrate depletion layer. Therefore, the SPBL both improved the vertical breakdown voltage (BVver) and suppressed an increase in the specific on-resistance (Ron,sp). The results of simulations showed a 14.46% higher TrBV and a 46.25% lower Ron,sp for the SPBL SOI LDMOS compared to those of the SOI LDMOS. As the SPBL optimized the vertical electric field at the drain, the turn-off non-breakdown time (Tnonbv) of the SPBL SOI LDMOS was 65.64% longer than that of the SOI LDMOS. The SPBL SOI LDMOS also demonstrated that TrBV was 10% higher, Ron,sp was 37.74% lower, and Tnonbv was 10% longer than those of the double RESURF SOI LDMOS.
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Martin, Annabel. "Utilisation du réseau Instagram pour le « Soin de soi » : Quelles implications pour les interventions de marketing social ?" Management & Avenir N° 142, no. 4 (September 20, 2024): 83–110. http://dx.doi.org/10.3917/mav.142.0083.
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Parmi les médias sociaux, Instagram est souvent positionné comme pouvant motiver des comportements de soin de soi tels qu’une activité physique régulière ou une consommation alimentaire saine et équilibrée. L’étude qualitative réalisée dans un premier temps identifie les apports perçus d’Instagram par les utilisatrices du média ainsi que leurs avis sur les contenus et les interactions sociales dans ce domaine. Elle se prolonge par le développement et le test d’un modèle dont les résultats confirment que la congruence des contenus avec le soi et l’authenticité perçue des interactions contribuent à la motivation de persévérance dans une activité de soin de soi, par l’intermédiaire et respectivement, d’une expansion de soi spécifique à l’activité et d’un sentiment de communauté. Les résultats confirment aussi que cette authenticité et ce sentiment motivent aux divulgations négatives de soi dans le but de recevoir ou d’apporter un soutien social aux efforts de changement comportemental. L’ensemble conduit aux préconisations pour les interventions de marketing social en termes de recrutement au compte d’intervention et de stratégie éditoriale et d’engagement média des personnes recrutées, ainsi que pour les communautés de pratique autour de hashtags et les groupes privés de changement comportemental, ou pour contrer des communications relatives au soin de soi mais risquées pour la santé.
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Choa, Sung Hoon, Moon Chul Lee, and Yong Chul Cho. "Effects of Packaging Induced Stress on MEMS Devices and Its Improvements." Key Engineering Materials 326-328 (December 2006): 529–32. http://dx.doi.org/10.4028/www.scientific.net/kem.326-328.529.
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In MEMS, packaging induced stress or stress induced structure deformation becomes increasing concerns since it directly affects the performance of the device. The conventional MEMS SOI (silicon-on-insulator) gyroscope, packaged using the anodic bonding at the wafer level and EMC (epoxy molding compound) molding, has a deformation of MEMS structure caused by thermal expansion mismatch. Therefore we propose a packaged SiOG (Silicon On Glass) process technology and more robust spring design.
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Novoselov, A. S., and N. V. Masalskii. "Influence of Hot Carrier Degradation on the Characteristics of a High-Voltage SOI Transistor with a Large Drift Region." Микроэлектроника 52, no. 5 (September 1, 2023): 423–30. http://dx.doi.org/10.31857/s0544126923700497.
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The results of studying the effect of hot carrier degradation on the electrical characteristics of high-power laterally diffused metal oxide semiconductor (LDMOS) transistors made according to the silicon-on-insulator (SOI) technology, with a long drift region with topological norms of 0.5 microns, are discussed. The analysis of the degradation of hot carriers in high electric fields is based on the experimental results and the additional use of an analytical model. The physical origin of this mechanism is related to the formation of traps at the Si/SiO2 interface. With the help of numerical analysis and experiments, the electrical character-istics of SOI nLDMOS transistors are considered in a wide range of control voltages in order to study their effect on the safe operation zone and reliability of the device under conditions of the degradation of hot carriers. The results of these studies allow us to conclude that a 20% expansion of the safe operation zone is possible.
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Froberger, Kevin, Benjamin Walter, Melanie Lavancier, Romain Peretti, Guillaume Ducournau, Jean-François Lampin, Marc Faucher, and Stefano Barbieri. "SOI-based micro-mechanical terahertz detector operating at room-temperature and atmospheric pressure." Applied Physics Letters 120, no. 26 (June 27, 2022): 261103. http://dx.doi.org/10.1063/5.0095126.
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We present a micro-mechanical terahertz (THz) detector fabricated on a silicon on insulator substrate and operating at room-temperature. The device is based on a U-shaped cantilever of micrometric size, on top of which two aluminum half-wave dipole antennas are deposited. This produces an absorption extending over the [Formula: see text] THz frequency range. Due to the different thermal expansion coefficients of silicon and aluminum, the absorbed radiation induces a deformation of the cantilever, which is read out optically using a 1.5 μm laser diode. By illuminating the detector with an amplitude modulated, 2.5 THz quantum cascade laser, we obtain, at room-temperature and atmospheric pressure, a responsivity of [Formula: see text] for the fundamental mechanical bending mode of the cantilever. This yields noise-equivalent-power of [Formula: see text] at 2.5 THz. Finally, the low mechanical quality factor of the mode grants a broad frequency response of approximately 150 kHz bandwidth, with a thermal response time of ∼ 2.5 μs.
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Chen, Siyuan, Jiaxin Qin, Yulan Lu, Bo Xie, Junbo Wang, Deyong Chen, and Jian Chen. "An All-Silicon Resonant Pressure Microsensor Based on Eutectic Bonding." Micromachines 14, no. 2 (February 13, 2023): 441. http://dx.doi.org/10.3390/mi14020441.
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In this paper, an all-Si resonant pressure microsensor based on eutectic bonding was developed, which can eliminate thermal expansion coefficient mismatches and residual thermal stresses during the bonding process. More specifically, the resonant pressure microsensor included an SOI wafer with a pressure-sensitive film embedded with resonators, which was eutectically bonded with a silicon cap for vacuum encapsulation. The all-Si resonant pressure microsensor was carefully designed and simulated numerically, where the use of the silicon cap was shown to effectively address temperature disturbances of the microsensor. The microsensor was then fabricated based on MEMS processes where eutectic bonding was adopted to link the SOI wafer and the silicon cap. The characterization results showed that the temperature disturbances of the resonant pressure microsensor encapsulated with the silicon cap were quantified as −0.82 Hz/°C of the central resonator and −2.36 Hz/°C of the side resonator within a temperature range from −40 °C to 80 °C, which were at least eight times lower than that of the microsensor encapsulated with the glass cap. Compared with the microsensor using the glass cap, the all-silicon microsensor demonstrated an accuracy improvement from 0.03% FS to 0.01% FS and a reduction in short-term frequency fluctuations from 3.2 Hz to 1.5 Hz.
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Pekarik, Jack, Vibhor Jain, Crystal Kenney, Judson Holt, Shweta Khokale, Sudesh Saroop, Jeffrey Johnson, et al. "Challenges for Sige Bicmos in Advanced-Node SOI." ECS Meeting Abstracts MA2022-02, no. 32 (October 9, 2022): 1196. http://dx.doi.org/10.1149/ma2022-02321196mtgabs.
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D-band (110-170GHz) spectrum is gaining attention for various applications, including 6G mm-Wave, sub-THz sensing, and radar. These systems require lattice spacing for antenna elements at sub-1mm and a very low loss signal path from antenna to integrated chip. A highly efficient front-end in a very small form factor will be required for these systems. This drives the requirement for a monolithically integrated high-gain, high-efficiency front-end that also leverages the benefits of a high-speed / high-density digital CMOS. Silicon germanium (SiGe) heterojunction bipolar transistors (HBT) integrated along with a high-density CMOS provide such an all-silicon monolithic solution. The US government is fostering the expansion of “unique and differentiated domestic manufacturing” with funding through DARPA’s Technologies for Mixed-mode Ultra Scaled Integrated Circuits (T-MUSIC) [1] program to enable disruptive RF mixed-mode technologies by developing high performance RF analog integrated with advanced digital CMOS. Through the T-MUSIC program, DARPA seeks to: 1) advance RF and mixed-mode devices to support ultra-wideband RF frontends from HF to 100 GHz; 2) integrate those devices with high density digital CMOS electronics at the wafer scale to enable embedded digital intelligence; 3) develop and explore ultra-high resolution broadband mixed-mode circuit building blocks for DoD-relevant applications; 4) explore innovative device topologies and materials to form THz devices in an advanced digital CMOS fabrication platform; and 5) establish a domestic ecosystem that facilitates enduring DoD access to differentiated capabilities for high performance RF mixed-mode SoCs. Under T-MUSIC, GlobalFoundries is demonstrating BiCMOS on 45nm PDSOI, which is the focus of this paper, and 22nm FDSOI CMOS with goals of increasing HBT performance of fT/fMAX from 350/500 GHz to 400/600 GHz and 600/700 GHz. HBTs with fT/fMAX of 380/550GHz GHz have been demonstrated building upon previously published results [2]. This paper will touch on some of the challenges that were encountered in achieving that result and discuss those anticipated in future work. Achieving these results required scaling transistor dimensions. Vertical scaling of the emitter, base and collector layers, with higher doping concentrations, reduces transit time but results in higher current densities and higher electric fields. Lateral scaling of the transistor structure reduces parasitic capacitance and resistance but concentrate the power dissipation in a smaller area. The thermal conductivity of silicon is 148W/m-K whereas that of silicon dioxide is ~1.4W/m-K. Even a thin layer of oxide will significantly increase the self-heating of the HBT. Therefore, we replace the SOI with coplanar epitaxy in regions where the HBTs are formed. The vertical scaling of the HBT requires limiting the thermal cycles that the HBT will experience during processing and suggests forming the HBT as late as possible in the CMOS process. However, the thermal cycles associate with the epitaxy and film depositions to form the HBT impact the CMOS transistors which suggests forming the HBT early in the process. We found a point in the process that offers the best compromise minimizing the impact to the doped-channel PDSOI CMOS while achieving the HBT performance goals. Work is just beginning on integration tradeoffs for FDSOI with metal gate and high-K dielectrics. Advanced-node CMOS processes can form components having smaller dimensions which offers advantages for lateral scaling but also presents challenges for forming the HBT. The contact height in 45nm is significantly less than the height of the HBT structure used in GF’s 9HP process. We changed the formation of the emitter and base so that the emitter and base contacts are almost coplanar in contrast to 9HP where the emitter was almost twice the height of the base. This problem is being further exasperated as we migrate to 22nm. The shrinking of BEOL wiring dimensions, along with the ability of the HBT to drive high currents, presents challenges in designing within limits imposed by electromigration. The use of wider wires is constrained by metal density rules. The use of stacked metal levels and redundant vias impact the parasitic capacitances and resistances of the interconnects. The paper and presentation will review these, and other challenges encountered in achieving BiCMOS integration of SiGe HBTs with fT/fMAX of 380/550GHz GHz [see figure] on a 45nm PDSOI CMOS and touch future work. This research was developed with funding from the Defense Advanced Research Projects Agency (DARPA) and is Approved for Public Release, Distribution Unlimited. The views, opinions and/or findings expressed are those of the author and should not be interpreted as representing the official views or policies of the Department of Defense or the U.S. Government. [1] https://www.darpa.mil/attachments/T-MUSIC_Proposers%20Day_Presentations_Combined.pdf [2] J. Pekarik et al., 2021 IEEE BCICTS, 2021, pp. 1-4, Figure 1
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Li, Haiwang, Yanxin Zhai, Zhi Tao, Yingxuan Gui, and Xiao Tan. "Thermal Drift Investigation of an SOI-Based MEMS Capacitive Sensor with an Asymmetric Structure." Sensors 19, no. 16 (August 12, 2019): 3522. http://dx.doi.org/10.3390/s19163522.
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High-precision, low-temperature-sensitive microelectromechanical system (MEMS) capacitive accelerometers are widely used in aerospace, automotive, and navigation systems. An analytical study of the temperature drift of bias (TDB) and temperature drift of scale factor (TDSF) for an asymmetric comb capacitive accelerometer is presented in this paper. A five-layer model is established for the equivalent expansion ratio in the TDB and TDSF formulas, and the results calculated by the weighted average of thickness and elasticity modulus method are closest to the results of the numerical simulation. The analytical formulas of TDB and TDSF for an asymmetric structure are obtained. For an asymmetric structure, TDB is only related to thermal deformation and fabrication error. Additionally, half of the fixed electrode distance is not included in the expressions of Δ d and Δ D for asymmetric structures, thus resulting in the TDSF of the asymmetric structure being smaller compared to a symmetric structure with the same structural parameters. The TDSF of the symmetric structure is [−200.2 ppm/°C, −261.6 ppm/°C], while the results of the asymmetric structure are [−11.004 ppm/°C, −72.404 ppm/°C] under the same set of parameters. The parameters of the optimal asymmetric structure are obtained for fabrication guidance using numerical methods. In the experiment, the TDSF and TDB of the packaged structure and the non-packaged structure are compared, and a significant effect of the package on the signal output is found. The TDB is reduced from 3000 to 60 μg/°C, while the TDSF is reduced from 3000 to 140 ppm/°C.
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Corrêa, Sergio Fernando M. "PARRESÍA E CINISMO COMO MODO DE VIDA: FOUCAULT E A AÇÃO POLÍTICA." Sapere Aude 10, no. 19 (July 14, 2019): 221–34. http://dx.doi.org/10.5752/p.2177-6342.2019v10n19p221-234.
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Este artigo busca analisar as relações e tensões entre parresía política e parresía cínica que Michel Foucault apresenta nos últimos cursos no Collège de France, a saber, Le gouvernement de soi et des autres e La courage de la vérité de 1983 e 1984. Partimos de duas noções de política em Foucault: política como estratégia de governamentalidade e política como resistência e insurreição. O texto se empenha em problematizar as formas institucionais de participação política e traz como hipótese principal que a forma de vida cínica pode oferecer um conteúdo importante para a ação política. A forma de vida cínica passa pela valorização da corporeidade, pela vida simples e desapegada e pelo distanciamento dos costumes culturais e políticos. A partir dessa descrição do cinismo pleiteamos uma ampliação da comunidade moral e política.PALAVRAS-CHAVE: Parresía. Cinismo, Democracia. Ação Política. Modo de Vida. ABSTRACTThis paper seeks to analyze the relations and tensions between political parrhesia and cynical parrhesia that Michel Foucault presents in his last years at the Collège de France, namely, Le gouvernement de soi et des autres de 1883 and La courage de la vérité de 1984. We start from two notions of politics in Foucault: politics as strategy of governmentality and politics as resistance and insurrection. The text tries to problematize the institutional forms of political participation and he brings as the main hypothesis that the cynical way of life can offer important content for political action. The cynical way of life goes through the valuation of corporeality, the simple and detached life and the distancing of cultural and political mores. From this description of cynicism, we plead for an expansion of the moral and political community.KEYWORDS: Parrhesia. Cynicism. Democracy. Political Action. Way of life.
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Locke, Christopher, Christopher L. Frewin, Jing Wang, and Stephen E. Saddow. "Growth of Single Crystal 3C-SiC(111) on a Poly-Si Seed Layer." Materials Science Forum 615-617 (March 2009): 157–60. http://dx.doi.org/10.4028/www.scientific.net/msf.615-617.157.
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A novel method for growing highly-crystalline 3C-SiC on an oxide release layer via a poly-Si seed layer is reported. Silicon carbide’s potential role as a ubiquitous material for MEMS fabrication lies in its dual role as an electronic and mechanical material. Unfortunately, due to residual stresses and crystal defects stemming from the large lattice constant mismatch and the thermal expansion coefficient difference between SiC and Si, the use of SiC in Si-based MEMS fabrication techniques has been very limited. The growth of 3C-SiC on a poly-Si seed layer deposited on oxide on (111)Si substrates (i.e., p-Si/ SiO2/(111)Si) provides an alternative fabrication method to expensive, traditional SOI bonding techniques for producing free-standing 3C-SiC MEMS structures. 3C-SiC grown with a poly-Si seed layer on SiO2 should experience reduced residual stress and far fewer defects due to the compliance of the SiO2 layer. Although poly-Si is utilized as a seed layer in this process, a well-ordered monocrystalline 3C-SiC layer was achieved and the process and film properties reported.
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Liang, Yanfeng, Huanlin Lv, Baichao Liu, Haoyu Wang, Fangxu Liu, Shuo Liu, Yang Cong, Xuanchen Li, and Qingxiao Guo. "Compact Low Loss Ribbed Asymmetric Multimode Interference Power Splitter." Photonics 11, no. 5 (May 17, 2024): 472. http://dx.doi.org/10.3390/photonics11050472.
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Optical power splitters (OPSs) are utilized extensively in integrated photonic circuits, drawing significant interest in research on power splitters with adjustable splitting ratios. This paper introduces a compact, low-loss 1 × 2 asymmetric multimode interferometric (MMI) optical power splitter on a silicon-on-insulator (SOI) platform. The device is simulated using the finite difference method (FDM) and eigenmode expansion solver (EME). It is possible to attain various output power splitting ratios by making the geometry of the MMI central section asymmetric relative to the propagation axis. Six distinct optical power splitters are designed with unconventional splitting ratios in this paper, which substantiates that the device can achieve any power splitter ratios (PSRs) in the range of 95:5 to 50:50. The dimensions of the multimode section were established at 2.9 × (9.5–10.9) μm. Simulation results show a range of unique advantages of the device, including a low extra loss of less than 0.4 dB, good fabrication tolerance, and power splitting ratio fluctuation below 3% across the 1500 nm to 1600 nm wavelength span.
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Fayolle, Jacky, and Paul-Emmanuel Micolet. "Cycles internationaux : éléments pour une problématique appliquée." Revue de l'OFCE 62, no. 3 (September 1, 1997): 109–50. http://dx.doi.org/10.3917/reof.p1997.62n1.0109.
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Résumé Le repérage et l'analyse des cycles concourent à la compréhension de l'histoire économique internationale. Ils permettent d'en expliciter les chronologies et les moments significatifs, qui se prêtent aux changements de Г organisation des rapports internationaux et dont l'issue peut infléchir durablement les perspectives de la croissance mondiale. Cet article propose un double repérage des cycles de croissance internationaux, soit comme intersection des cycles nationaux élémentaires, soit comme cycles spécifiques d'agrégats internationaux, comme le commerce international. Des indicateurs de diffusion et de synchronisation des cycles conjoncturels au sein de l'OCDE et de l'Europe sont élaborés pour apprécier les degrés de généralisation et de simultanéité d'une expansion, d'une récession ou d'une situation de retournement à l'échelle internationale. La comparaison des différents repérages des cycles internationaux montre que ceux-ci ont étroitement partie liée avec les rythmes de l accumulation du capital à l'échelle mondiale. Ces cycles internationaux ne se propagent pas au sein d'une économie mondiale parfaitement homogène. Les croissances potentielles de long terme des différentes nations peuvent différer, ce qui témoigne, notamment, de phénomènes de rattrapage. L'harmo-nisation conjoncturelle des croissances potentielles nationales ne va pas de soi et peut être à l'origine de tensions et de retournements cycliques lorsqu'elle s'avère insuffisamment accommodante à l 'égard des expansions nationales. De plus, tous les pays, même à s'en tenir aux pays de l'OCDE, ne manifestent pas la même propension aux fluctuations cycliques, ni la même régularité de ces fluctuations. Une typologie des pays, en fonction de leurs propriétés cycliques, peut être esquissée. L'impulsion et la propagation des fluctuations à l 'échelle internationale ne peuvent être pleinement comprises sans la prise en compte de cette hétérogénéité. C'est aussi cette dépendance du comportement cyclique de l'économie internationale à l'égard de ses structures concrètes, qui rend difficile la synthèse historique des régularités susceptibles de le caractériser.
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Torres, David, LaVern Starman, Harris Hall, Juan Pastrana, and Sarah Dooley. "Design, Simulation, Fabrication, and Characterization of an Electrothermal Tip-Tilt-Piston Large Angle Micromirror for High Fill Factor Segmented Optical Arrays." Micromachines 12, no. 4 (April 12, 2021): 419. http://dx.doi.org/10.3390/mi12040419.
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Micro-electromechanical system (MEMS) micromirrors have been in development for many years, but the ability to steer beams to angles larger than 20° remains a challenging endeavor. This paper details a MEMS micromirror device capable of achieving large motion for both tip/tilt angles and piston motion. The device consists of an electrothermal actuation assembly fabricated from a carefully patterned multilayer thin-film stack (SiO2/Al/SiO2) that is epoxy bonded to a 1 mm2 Au coated micromirror fabricated from an SOI wafer. The actuation assembly consists of four identical actuators, each comprised of a series of beams that use the inherent residual stresses and coefficient of thermal expansion (CTE) mismatches of the selected thin films to enable the large, upward, out-of-plane deflections necessary for large-angle beamsteering. Finite element simulations were performed (COMSOL v5.5) to capture initial elevations and tip/tilt motion displacements and achieved <10% variance in comparison to the experiment. The measured performance metrics of the micromirror include tip/tilt angles of ±23°, piston motion of 127 µm at sub-resonance, and dynamics characterization with observed resonant frequencies at ~145 Hz and ~226 Hz, for tip/tilt and piston motion, respectively. This unique single element design can readily be scaled into a full segmented micromirror array exhibiting an optical fill-factor >85%, making it suitable for optical phased array beam control applications.
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Setiawan, Ardhika, and Ocktaeck Lim. "Combustion Characteristic Prediction of Dual Direct Injection Fuel (Diesel-Propane) on RCEM Based on an Artificial Neural Network Approach." International Journal of Energy Research 2024 (April 12, 2024): 1–19. http://dx.doi.org/10.1155/2024/3395861.
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Studies from around the world show that engines using biofuel, LPG, and CNG emit fewer pollutants than those using conventional fuels. Experimental research has focused on a rapid compression and expansion machine (RCEM) that resembles a compression ignition (CI) engine. It uses dual direct injection fuel, diesel and propane (DP), with propane injection timing varying from 0 to 40 before top dead center (BTDC) and diesel injection timing remaining at 10 BTDC. The compression ratio was changed at points 17 and 19 by adjusting the RCEM connecting rod. A converge simulation program was used to run the simulation model, which was used to examine how the fire and inflow inside the chamber developed. The ANN method was used to predict pressure, temperature, power, TKE, and ITE data output based on propane energy fraction, compression ratio, and SOI of propane as input data parameters. It was noticed that the ANN prediction on experimental data has a higher accuracy compared to the simulation prediction. The R and MSE values were used to identify the accuracy of the prediction on output parameter data. ANN generalization capability is comparatively high when trained with large enough databases. The highest accuracy of prediction was produced on TKE, which had an MSE of 0.003715 and R value of 0.99981 from 287900 sample data. This shows that the ANN model is quite accurate in forecasting output experimental data.
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Prado Jr., Plínio W. "A DESORIENTAÇÃO GERAL." Revista Observatório 4, no. 2 (April 1, 2018): 995. http://dx.doi.org/10.20873/uft.2447-4266.2018v4n2p995.
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Este ensaio se interroga sobre a situação de impasse geral na qual vivemos no momento presente, devido à crise profunda da política ocidental moderna e, portanto, da condição histórica ela mesma, enquanto promessa de emancipação dos sujeitos. A falta geral de horizonte, o desaparecimento de um verdadeiro projeto crítico, histórico-político, o vazio de sentido que uma política reduzida à gestão do sistema liberal deixa na sua ruína, caracterizam esse impasse. A questão atual é portanto a da desorientação geral. Esta define o motivo condutor o mais apto a reunir e a articular os diferentes fios dos eventos que tramam hoje o nosso destino. Estes fios trazem todos a marca da ameaça. Que seja a expansão e a intensificação dos atentados do salafismo djihadista na França, na Europa, nos EUA, e a dita “co-radicalização” correspondente da extrema direita islamofóbica; ou o crescimento atual das novas extremas direitas populistas; ou ainda a “política das coisas” do próprio sistema ocidental, reduzindo a política em administração e elegendo a segurança como técnica de governo. Estas ameaças não são todas da mesma espécie, evidentemente, nem se equivalem. No entanto todas têm em comum o fato de atacar em última análise, para lá das solidariedades coletivas, a vida subjetiva, singular, o si. Ou seja, mais precisamente, a relação de si consigo mesmo e com o outro de si, por meio da qual somente um sujeito pode manter uma “linha geral” ao longo de sua existência. De forma que, sob as ameaças diversas, o sujeito perde e se perde (se desorienta) em todas as frentes de luta. Desprovido de sua relação a si, o sujeito ameaçado tende a ser minado : conduzido, dirigido, gerido. última bússola do sobrevivente na época que corre : os recursos do labor que consiste a reatar uma relação de si consigo mesmo e com o outro de si, condição e princípio de toda orientação possível. última forma capaz de opor uma resistência ao tempo presente. Elaborar esses recursos, perlaborá-los, tal é, hoje como ontem, a tarefa da arte, da literatura, do pensamento.
PALAVRAS-CHAVE: Arte; outro (de si); destino; djihadista; emancipação; existência; extrema direita.
RESUME
L'essai s’interroge sur la situation de grave impasse générale dans laquelle le monde se trouve aujourd'hui. Cette impasse est présentée comme engendrée par la crise profonde de la politique occidentale moderne, et partant de sa perspective historique, comprise comme promesse d'émancipation des sujets. Le manque général d'horizon historico-politique, la disparition d'un véritable projet critique, le vide de sens qu'une politique réduite à la gestion du système libéral engendre dans sa ruine, caractérisent cette impasse. La question actuelle est donc bien celle de la désorientation générale. Cela définit le motif conducteur le plus apte à rassembler et à articuler les différents fils des événements qui tracent notre destin aujourd'hui. Ces fils portent tous la marque de la menace : que ce soit l'expansion et l'intensification des attaques du salafisme djihadiste en France, en Europe ou aux États-Unis, et ladite « co-radicalisation » de l’extrême droite islamophobe ; ou la croissance actuelle de nouvelles extrêmes droites populistes ; ou la « politique des choses » (la nouvelle technocratie) du système occidental lui-même, réduisant la politique à la gestion des affaires du système et choisissant « la sécurité » comme technique de gouvernement. Ces menaces ne sont pas toutes de même nature, bien sûr, et ne s’équivalent pas. Cependant, elles ont toutes en commun le fait d'attaquer en dernière analyse, au-delà des solidarités collectives, la vie subjective, singulière : le soi. C'est-à-dire, plus précisément : la relation de soi à soi-même et à l'autre de soi, suivant laquelle seulement un sujet peut s’esquisser [se dessiner lui-même] et maintenir une « ligne générale » au long de son existence. De sorte que, sous ces différentes menaces, le sujet perd et se perd (se désoriente) sur tous les fronts de la lutte, sur tous les tableaux. Dépouillé de sa relation à lui-même, le sujet menacé tend à être complètement miné : mené, dirigé, géré tout au long de son existence. Il s’ensuit la dernière boussole du survivant, dans l'époque qui court : celle que fournissent les ressources du travail qui consiste à reprendre une relation de soi avec soi-même et avec l'autre de soi, condition et principe de toute orientation possible. Ultime forme capable d'opposer une résistance au temps présent. Or, élaborer ces ressources, les perlaborer, c'est précisément la tâche de l'art, de la littérature, de la pensée.
MOTS-CLÉS: art; autre (de soi); destin; djihadiste; émancipation; existence; extrême droite.
ABSTRACT
The essay questions the situation of serious global impasse in which the world is today. This impasse is portrayed as engendered by the deep crisis of modern Western politics, and of its historical perspective, understood as a promise of emancipation of subjects. The general lack of a historical-political horizon, the disappearance of a true critical project, the meaningless that a policy reduced to the management of the liberal system engenders in its ruin, characterize this impasse. The question today is therefore that of a general disorientation. This defines the leitmotiv for gathering and articulating the different threads of events that map out our destiny today. These threads all bear the mark of the threat: that it is the expansion and the intensification of attacks of the Jihadist salafist in France, Europe or the United States, and the "co-radicalization" of the Islamophobic far right; or the current growth of new populists far right; or the "politics of things" (the new technocracy) of the Western system itself, reducing politics to the management of the system's affairs and choosing "security" as a technique of government. These threats are not all of the same nature, of course, and they are not equivalent. However, they all have in common the fact of attacking, in the last analysis, beyond collective solidarities, the subjective, singular life: the self. That is to say, more precisely: the relation of oneself to oneself and to the other of oneself, according to which only a subject can to draw oneself and maintain a "general line" throughout his life. So, under these different threats, the subject loses and loses (disorients) oneself on all fronts of the struggle. Stripped of its relation to itself, the threatened subject tends to be completely undermined: led, directed, managed throughout its existence. It follows the last compass of the survivor, in the time that is running: that provided by the resources of work which consists in taking up a relationship of oneself with oneself and with the other of oneself, a condition and principle of any possible orientation. Ultimate form able to oppose a resistance to the present time. Now, to elaborate these resources, to working-through them, is precisely the task of art, of literature, of thought.
KEYWORDS: art; other (of oneself); destiny; jihadist; emancipation; existence ; far right.
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Rato Martín, Héctor. "La iniciativa privada como impulsora de la construcción de la ciudad burguesa. Parcelaciones particulares en Llanes (1850-1960) / The private initiative as a promoter of bourgeois city. Private parceling in Llanes (1850-1960)." Ería 3, no. 3 (November 26, 2019): 351–66. http://dx.doi.org/10.17811/er.3.2019.353-368.
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A partir de mediados del siglo xix se agotó en España el modelo urba- no del Antiguo Régimen y emergió la denominada ciudad burguesa. Los cambios se concretaron en la transformación de la trama heredada y en la ampliación de su plano. El papel de la iniciativa privada se concretó habitualmente en la producción de suelo urbano mediante la parcelación de tierras de su propiedad. El artículo analiza la formación de la ciudad burguesa en la villa de Llanes atendiendo al papel de la iniciativa particular en la expansión de su plano entre 1850 y 1960. Se describen las características de las parcelaciones identificadas, estableciendo su rasgos generales y contextualizándolas en los procesos de carácter general.À partir du milieu du xixe siècle, le modèle urbain de l’Ancien Régime était épuisé en Espagne et la soi-disant ville bourgeoise a émergé. Les changements ont pris forme dans la transformation du plan hérité et son extension. Le rôle de l’initiative privée s’est généralement concrétisé dans la production de sol urbain grâce à la division des terrains qu’elle possédait. L’article analyse la formation de la ville bourgeoise à Llanes (Asturies orientales) en se concentrant sur le rôle de l’initiative privée dans l’expansion du plan entre 1850 et 1960. Les caractéristiques des parcellisations identifiées sont décrites, en établissant leurs traits principaux et en les contextualisant dans les processus généraux.From the mid-nineteenth century the urban model of the Old Regime was exhausted in Spain and the so-called bourgeois city emerged. The changes took shape in the transformation of the inherited plot and in the extension of its plan. The role of private initiative was usually the production of urban land through the division of its properties. The article analyzes the formation of the bourgeois city in Llanes (Eastern Asturias), taking into account the role of the private initiative in the expansion of the plan between 1850 and 1960. The characteristics of parceling are described, establishing their general features and contextualizing them in general processes.
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Besancon, Claire, Delphine Néel, Dalila Make, Joan Manel Ramírez, Giancarlo Cerulo, Nicolas Vaissiere, David Bitauld, et al. "AlGaInAs Multi-Quantum Well Lasers on Silicon-on-Insulator Photonic Integrated Circuits Based on InP-Seed-Bonding and Epitaxial Regrowth." Applied Sciences 12, no. 1 (December 28, 2021): 263. http://dx.doi.org/10.3390/app12010263.
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The tremendous demand for low-cost, low-consumption and high-capacity optical transmitters in data centers challenges the current InP-photonics platform. The use of silicon (Si) photonics platform to fabricate photonic integrated circuits (PICs) is a promising approach for low-cost large-scale fabrication considering the CMOS-technology maturity and scalability. However, Si itself cannot provide an efficient emitting light source due to its indirect bandgap. Therefore, the integration of III-V semiconductors on Si wafers allows us to benefit from the III-V emitting properties combined with benefits offered by the Si photonics platform. Direct epitaxy of InP-based materials on 300 mm Si wafers is the most promising approach to reduce the costs. However, the differences between InP and Si in terms of lattice mismatch, thermal coefficients and polarity inducing defects are challenging issues to overcome. III-V/Si hetero-integration platform by wafer-bonding is the most mature integration scheme. However, no additional epitaxial regrowth steps are implemented after the bonding step. Considering the much larger epitaxial toolkit available in the conventional monolithic InP platform, where several epitaxial steps are often implemented, this represents a significant limitation. In this paper, we review an advanced integration scheme of AlGaInAs-based laser sources on Si wafers by bonding a thin InP seed on which further regrowth steps are implemented. A 3 µm-thick AlGaInAs-based MutiQuantum Wells (MQW) laser structure was grown onto on InP-SiO2/Si (InPoSi) wafer and compared to the same structure grown on InP wafer as a reference. The 400 ppm thermal strain on the structure grown on InPoSi, induced by the difference of coefficient of thermal expansion between InP and Si, was assessed at growth temperature. We also showed that this structure demonstrates laser performance similar to the ones obtained for the same structure grown on InP. Therefore, no material degradation was observed in spite of the thermal strain. Then, we developed the Selective Area Growth (SAG) technique to grow multi-wavelength laser sources from a single growth step on InPoSi. A 155 nm-wide spectral range from 1515 nm to 1670 nm was achieved. Furthermore, an AlGaInAs MQW-based laser source was successfully grown on InP-SOI wafers and efficiently coupled to Si-photonic DBR cavities. Altogether, the regrowth on InP-SOI wafers holds great promises to combine the best from the III-V monolithic platform combined with the possibilities offered by the Si photonics circuitry via efficient light-coupling.
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Yuge, R., A. Toda, K. Fukatsu, N. Tamura, T. Manako, K. Nakahara, and K. Nakano. "Effect of Volume Expansion on SEI Covering Carbon-Coated Nano-Si/SiO Composite." Journal of The Electrochemical Society 160, no. 10 (2013): A1789—A1793. http://dx.doi.org/10.1149/2.075310jes.
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Liu, Tao, Ling Zhang, and Borong Wu. "Modifying SiO @ C as High-performance Anode of Lithium-ion Batteries." Journal of Physics: Conference Series 2563, no. 1 (August 1, 2023): 012015. http://dx.doi.org/10.1088/1742-6596/2563/1/012015.
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Abstract SiO is a widely prospected anode material, which is an excellent substitute for pure silicon for lithium-ion batteries in the future, with the reason of lower expansion degree. However, the conductivity of SiO is also poor and has a side reaction with electrolytes. Here, we choose melamine as a nitrogen source to modify the carbon layer-coated SiO materials. This study shows that nitrogen and carbon shells lead to forming stable SEI, and improve the conductivity of the anodes. Consequently, at 0.1 C, the modified SiO materials in the anode achieve an excellent specific capacity (1711.5 mAh g-1), in addition, the decay rate of the capacity is 0.6% per cycle in the next 100 cycles. This method makes a new direction for the product of SiO materials.
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Fuentes, Rudy, Yuhuan Wang, and Mortimer Poncz. "Expansion of Platelets for Transfusion." Blood 116, no. 21 (November 19, 2010): SCI—47—SCI—47. http://dx.doi.org/10.1182/blood.v116.21.sci-47.sci-47.
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Abstract Abstract SCI-47 The clinical need for platelets transfusion continues to grow. Platelet units have all the usual concerns with other donor-derived blood products and in addition have concerns over the need to store the platelets at room temperature and of the resulting increased risk of bacterial contamination. Several groups have been able to develop platelets from embryonic stem cells, but achieving significant numbers of pro-platelets and/or platelets from in vitro grown megakaryocytes (Megs) remains elusive. Three sites of thrombopoiesis in vivo have been described: 1) intramedullary, 2) at the medullary/vascular junction, or 3) intrapulmonary from circulating Megs. We investigated whether infusing murine Megs into mice can release a large number of functional platelets both to better understand thrombopoiesis and also to see if such an approach may be an alternative to generating platelets for clinical usage. We show that infused fetal-liver-derived Megs results in 100–200 platelets/Meg. Levels as high as 12% of the total platelets in the recipient mouse were from the infused Megs. These platelets had a delayed presentation, peaking at 90 mins. In spite of these being new platelets, their half-life was only ∼75% of infused platelets. The shortened half-life was not due to the fact that these platelets were fetal in nature in that infused adult-liver-derived Megs had a similar temporal profile. These derived platelets had normal-size distribution, were not activated, and had not been affected by ADAM17 during in vitro culture as determined by surface glycoprotein 1b alpha. Platelet functionality was shown by their incorporation into clots in arterioles and venules in a cremaster laser injury model and in a ferric chloride carotid artery injury model. Using BrdU-labeled Megs we show that most of the Megs are trapped in the lungs with a few also appearing in the splenic red pulp. None were seen in other tissues. Staining with species-specific CD41 antibodies showed that detectable Meg cytoplasm peaked in the pulmonary vasculature at 30 min, and like the nuclei, was mostly gone by 5 hrs. We estimate that only ∼1% of the available pulmonary capillary bed is affected by the infused Megs, and most studied animals survived the infusion of the Megs. These studies support the lungs as a potential site for thrombopoiesis and that in vitro differentiated Megs can be infused directly avoiding the challenge of developing ex vivo technology to release large number of non-activated, but functional platelets. Disclosures: No relevant conflicts of interest to declare.
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Xiong, Lujie, Fengwei Wang, and Yanping Jiao. "Regional Sea Level Changes in the East China Sea from 1993 to 2020 Based on Satellite Altimetry." Journal of Marine Science and Engineering 12, no. 9 (September 5, 2024): 1552. http://dx.doi.org/10.3390/jmse12091552.
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A comprehensive analysis was carried out to investigate the driving factors and influencing mechanisms of spatiotemporal variation of sea level at multiple scales in the East China Sea (ECS) via satellite altimetry datasets from 1993 to 2020. Based on the altimetry grid data processed by the local mean decomposition method, the spatiotemporal changes of ECS sea level are analyzed from the multi-scale perspective in terms of multi-year, seasonal, interannual, and multi-modal scales. The results revealed that the ECS regional mean sea level change rate is 3.41 ± 0.58 mm/year over the 28-year period. On the seasonal scale, the regional mean sea level change rates are 3.45 ± 0.66 mm/year, 3.35 ± 0.60 mm/year, 3.39 ± 0.71 mm/year, and 3.57 ± 0.75 mm/year, for the four seasons (i.e., spring, summer, autumn, and winter) respectively. The spatial distribution analysis showed that ECS sea level changes are most pronounced in coastal areas. The northeast sea area of Taiwan and the edge of the East China Sea shelf are important areas of mesoscale eddy activity, which have an important impact on regional sea level change. The ECS seasonal sea level change is mainly affected by monsoons, precipitation, and temperature changes. The spatial distribution analysis indicated that the impact factors, including seawater thermal expansion, monsoons, ENSO, and the Kuroshio Current, dominated the ECS seasonal sea level change. Additionally, the ENSO and Kuroshio Current collectively affect the spatial distribution characteristics. Additionally, the empirical orthogonal function was employed to analyze the three modes of ECS regional sea level change, with the first three modes contributing 26.37%, 12.32%, and 10.47%, respectively. Spatially, the first mode mainly corresponds to ENSO index, whereas the second and third modes are linked to seasonal factors, and exhibit antiphase effects. The analyzed correlations between the ECS sea level change and southern oscillation index (SOI), revealed the consistent spatial characteristics between the regions affected by ENSO and those by the Kuroshio Current.
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Sauvageau, Guy. "Manipulating Stem Cells for Therapeutic Expansion." Blood 114, no. 22 (November 20, 2009): SCI—42—SCI—42. http://dx.doi.org/10.1182/blood.v114.22.sci-42.sci-42.
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Abstract Abstract SCI-42 “Self-renewal” is a process central to the expansion of normal and cancerous stem cells and its understanding is critical for future advances in transplantation-based therapies and cancer treatment. Even today, many patients are deprived of the benefit of a successful blood stem cell transplant because the number of allogeneic or autologous stem cells available is insufficient, which results in delayed hematopoietic recovery post-transplant, or exclusion of a transplant-based therapeutic option altogether. The molecular machinery controlling self-renewal of hematopoietic stem cells (HSCs) remains poorly defined with the exception of a few genes such as HOX4 and Bmi1. We and others recently demonstrated the capacity of a recombinant HOXB4 protein (TAT-HOXB4 fusion protein) to stimulate mouse and human HSC self-renewal divisions in culture. Technical difficulties inherent to this recombinant protein have postponed the initiation of clinical trials. In part to overcome this hurdle, we have developed a novel in vitro/in vivo gain-of-function screen and identified several nuclear factors which expand hematopoietic stem cell ex vivo. A significant proportion of these factors display HOXB4-like properties and show non-cell autonomous activity. Initial results suggest that some of these new factors are also active with human cord blood derived HSCs. The generation of novel TAT fusion proteins will open new possibilities in the therapeutic expansion of human HSCs. Disclosures No relevant conflicts of interest to declare.
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Migliaccio, Anna Rita F., Carolyn Whitsett, and Giovanni Migliaccio. "Expansion of Red Blood Cells for Transfusion." Blood 116, no. 21 (November 19, 2010): SCI—46—SCI—46. http://dx.doi.org/10.1182/blood.v116.21.sci-46.sci-46.
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Abstract Abstract SCI-46 Blood transfusion, the earliest form of cell replacement therapy, has become indispensable for modern medicine making the safety and adequacy of the blood supply a national priority. The US blood supply is adequate overall because in 2006 the number of blood units collected exceed by 7.8% the number of those transfused. However, issues surrounding blood transfusion, such as sporadic shortages and potential adverse events to recipients (related to changes in red cell physiology during storage and alloimmunization in chronically transfused patients) prompted past and current efforts to develop alternative transfusion products. Recently, the culture conditions to generate erythroid cells have greatly improved making the production of a transfusion product ex-vivo a theoretically possible, although expensive, proposition. This recognition is inspiring several investigators to develop production processes for ex-vivo generation of red cell transfusion products. A proof-of-concept demonstrating that ex-vivo generated red cells protect mice from experimentally induced lethal anemia has been obtained. Alternative sources of stem cells which include human embryonic stem cells (hESC) and induced pluripotency stem cells (iPS), are being explored. Since red cells do not have a nucleus, safety considerations suggest that they may represent the first cell therapy product to be generated from hESC and iPS. In addition, discarded hematopoietic stem cells present in adult and cord blood donations may theoretically generate numbers of red cells ex-vivo sufficient for transfusion. Affordable clinical grade humanized culture media have also been developed. Possible differences in immunological and biological properties of erythroid cells from different sources are under investigation. These differences include size, levels of activity of glycolytic enzymes and carbonic anhydrase, expression of different isozymes, hemoglobin and antigenic profiles (HLA class II antigens). This last aspect is particularly important because ex-vivo expanded red cells pose the same risk for infection and incompatibility as any transfusion product but pose unique antigenic risks. Since expression of blood group antigens is susceptible to post-transcriptional modifications, the ex-vivo expansion process itself may induce antigenic variability. Therefore, even cells generated from completely matched stem cell sources may induce auto-immunity and/or appear incompatible. Regarding the identity of ex-vivo generated red cell transfusion products, a conservative approach would be to define them as “enucleated red cells”. In principle, however, ex-vivo generated erythroblasts may also serve as transfusion product. Since they undergo 4–64 further divisions and reduce iron overload, they may represent a more potent transfusion product for patients that require chronic transfusion. The clinical use of these cells, however, may involve development of specific procedures to facilitate their homing/maturation in the erythroid niches of the recipients. In summary, on the basis of these cost, logistic and safety considerations we hypothesize that the clinical application of ex-vivo expanded erythroblasts will involve in sequence, drug discovery for personalized therapy, systemic drug delivery, genotypically matched transfusion for alloimmunized patients and then transfusion in the general population. Disclosures: No relevant conflicts of interest to declare.
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Heslop, Helen E. "Expansion of Lymphocytes for Cell-Based Therapeutics." Blood 116, no. 21 (November 19, 2010): SCI—48—SCI—48. http://dx.doi.org/10.1182/blood.v116.21.sci-48.sci-48.
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Abstract Abstract SCI-48 Adoptive transfer of T cells can lead to targeted and long-lived anti-tumor or anti-infective activity and can also modulate alloreactivity. T cell therapies have been used in both autologous and allogeneic settings. Donor-derived cytotoxic specific T lymphocytes (CTLs) have already proved highly effective in preventing or treating viral infections and Epstein-Barr virus (EBV) lymphomas developing after allogeneic hemopoietic stem cell transplant while T cells expanded ex vivo with CD3/28 beads have enhanced immune reconstitution after autologous stem cell transplantation. Clinical responses have also been observed following T cell therapy in patients with melanoma, lymphoma or nasopharyngeal cancer. Although successes have been obtained, these studies have also provided insights into the requirements for more effective cellular immunotherapy, which may be obtained by genetic modification of T cells. Approaches under evaluation in the clinic include transfer of artificial T cell receptors to target tumor cells, transfer of genes to render T cells resistant to tumor evasion mechanisms and transfer of a suicide gene that can be activated should adverse effects occur to allow the cell to be destroyed on exposure to a specific signal. The suicide gene strategy using the herpes simplex viral thymidine kinase (Tk) gene allows ablation of infused donor T cells if they induce graft-versus-host disease after allogeneic HSCT and has reached phase III clinical trial. In all these adoptive T cell immunotherapy strategies, broader application is limited by suboptimal persistence of transferred T cells, and by the complexity of current manufacturing techniques. Current research focuses on defining the optimum type of cell for transfer and the ex vivo selection and expansion procedures that favor long term persistence, since broader applicability will require ex vivo expanded T cells to show clinical activity and to have robust manufacturing processes and a clinical distribution paradigm. Strategies for simplifying and accelerating manufacture of T cell products have included the use of artificial antigen presenting cells expressing co-stimulatory ligands to provide a rapid source of antigen and optimized costimulation; bioreactors to grow cells in a closed system; and cytokine combinations to optimize cell growth and survival. Integration of these multiple approaches will be required to determine the best cell type and culture conditions for generating T cells for subsequent adoptive transfer into a complex immune network. Disclosures: Off Label Use: T cell products in studies conducted under INDs.
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Cooke, Michael P., and Anthony E. Boitano. "Small Molecule Screens for Stem Cell Expansion." Blood 118, no. 21 (November 18, 2011): SCI—42—SCI—42. http://dx.doi.org/10.1182/blood.v118.21.sci-42.sci-42.
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Abstract SCI-42 The identification of safe and effective methods to expand human hematopoietic stem cells (HSC) would have a major impact on the use of HSC in clinical medicine. Several features of human HSC, including the lack of a suitable cell line model and cumbersome methods for quantification, have made the identification of conditions for human HSC expansion challenging. Current culture methods using cytokine cocktails in serum-free media support the robust proliferation of CD34 positive (CD34+) cells but this is accompanied by rapid differentiation such that after 1 week of culture fewer than 20% of cells continue to express CD34. To overcome these limitations we developed a high throughput screen that uses primary human CD34+ cells and multiparameter flow cytometry to identify compounds capable of expanding human CD34 positive cells. By screening >100,000 LMW compounds we identified a molecule (SR1) that enhanced CD34 expression during ex vivo culture. Culture of CD34+ cells with cytokines and SR1 for 3 weeks leads to a >600-fold increase in the number of CD34+ cells, and a >2000-fold increase in the number of CFU compared to starting cell numbers. Importantly, cells expanded in the presence of SR1contain a 17-fold increase in the number of NOD-SCID repopulating cells compared to starting cell numbers. Mechanistic studies reveal that SR1 binds to and antagonizes the aryl hydrocarbon receptor (AHR). Knockdown of the AHR in CD34+ cells using lentiviral transduction also maintains CD34 expression. These findings suggest that AHR normally promotes HSC differentiation during ex vivo culture and that AHR antagonists can be used to promote CD34 cell expansion. To determine the clinical utility of these findings, we have begun to explore the use of SR1 to expand CD34+ cells isolated from umbilical cord blood for clinical transplantation. To this end, we have developed a GMP compatible process to manufacture CD34 positive cells expanded with SR1 for use in cord blood transplantation. In addition, we have also explored the use of SR1 to prevent HSC differentiation during HSC transduction and enable manufacturing of differentiated blood cells. These data reveal AHR antagonism and SR1 treatment as a promising method to promote HSC expansion for clinical use. Disclosures: Cooke: Novartis: Employment. Boitano:Novartis: Employment.
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Li, Bei Xing, Da Ke, Ji Hong Song, and Ke Jian Fu. "Effect of Gypsum-Contaminated Aggregate on Long Term Properties of Mortar." Advanced Materials Research 450-451 (January 2012): 205–9. http://dx.doi.org/10.4028/www.scientific.net/amr.450-451.205.
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Contamination of aggregates with gypsum occurs frequently. Fine aggregate has more detrimental effect due to its large surface area. An experimental work had carried out to investigate the behavior of mortar made from six SO3 contents in the fine aggregate, five size fractions of gypseous aggregate and three C¬3A contents in the cement. The results show that significant expansions do not occur within mortar bars if the content of SO3 lies below 1.25% by the weight of fine aggregate and the reduction in strength is higher in later ages and for higher SO3 contents. The size fraction of gypseous aggregate also affects the degree of expansion, especially in the case of fine particles. The cement with C3A content lower than 5% can tolerate a higher level of contaminant gypsum.
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Weng, Andrew, Everardo Olide, Vivian Tran, Iaroslav Kovalchuk, Jason Siegel, and Anna Stefanopoulou. "Phenomenological Model of SEI Formation and Growth Leveraging Real-Time Expansion Measurements." ECS Meeting Abstracts MA2023-01, no. 25 (August 28, 2023): 1666. http://dx.doi.org/10.1149/ma2023-01251666mtgabs.
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Every commercial lithium-ion battery undergoes formation at the end of the manufacturing process [1]. The formation process is time and capital-intensive, motivating battery manufacturers to develop new formation recipes to decrease formation time while preserving battery lifetime and safety [2]. Yet, despite its importance, a general framework for modeling formation of commercial lithium-ion battery systems is lacking, hindering the innovation cycle. While first-principles solid electrolyte interphase (SEI) formation modeling approaches exist [3], such models are often computationally expensive and challenging to validate, limiting their application towards predicting macroscopic variables relevant to commercial lithium-ion batteries such as capacity loss and resistance growth over life. Semi-physics based (i.e. semi-empirical, or phenomenological) approaches are popular [4], but such models are often parameterized using cell data collected after formation has already completed, making them unsuitable for capturing the initial stages of the SEI formation process. This work presents a framework for developing semi-physics based models of SEI formation and growth dynamics for use in commercial lithium-ion battery systems. The model enables real-time prediction of lithium consumption during the formation (i.e. first charge) process, which can be extended to track the lithium consumption over the entire lifespan of the cell. By explicitly considering the electrolyte reduction reaction dynamics during the first cycle, the model enables the study of how different formation protocols influence SEI passivation properties [5] and hence battery lifetime. The model leverages half-cell near-equilibrium potential curves to track the evolution of lithium stoichiometries and electrode potentials at each electrode, during and after the formation process. The model thus enables real-time tracking of the SEI-forming electrolyte reduction rates which can be used to estimate the quantity of lithium consumed to create the SEI. Model parameters are tuned against experimental electrode expansion measurements collected on NMC622|graphite pouch cells (Figure 1), which resolves both the reversible (i.e. lithiation-induced) and irreversible sources of electrode expansion [6],[7]. Model-predicted lithium consumption rates and electrode expansions are validated against an experimental dataset consisting of three different formation protocols which includes cycle life testing until the end of life. The modeling framework we propose enables practical pathways for bridging the electrochemistry of battery formation to macroscopic variables related to battery safety and lifetime, including total capacity loss, resistance growth, gas generation (during SEI and due to electrolyte oxidation at the positive electrode), and copper dissolution rates. [1] S. J. An, J. Li, C. Daniel, D. Mohanty, S. Nagpure, and D. L. Wood, “The state of understanding of the lithium-ion-battery graphite solid electrolyte interphase (SEI) and its relationship to formation cycling,” Carbon N. Y., vol. 105, pp. 52–76, 2016. [2] Y. Liu, R. Zhang, J. Wang, and Y. Wang, “Current and future lithium-ion battery manufacturing,” iScience, vol. 24, p. 102332, Apr. 2021. [3] A. Wang, S. Kadam, H. Li, S. Shi, and Y. Qi, “Review on modeling of the anode solid electrolyte interphase (SEI) for lithium-ion batteries,” npj Computational Materials, vol. 4, no. 1, 2018. [4] L. von Kolzenberg, J. Stadler, J. Fath, M. Ecker, B. Horstmann, and A. Latz, “A four parameter model for the solid-electrolyte interphase to predict battery aging during operation,” J. Power Sources, vol. 539, p. 231560, Aug. 2022. [5] P. M. Attia, S. J. Harris, and W. C. Chueh, “Benefits of fast battery formation in a model system,” J. Electrochem. Soc., vol. 168, no. 5, p. 050543, 2021. [6] P. Mohtat, S. Lee, J. B. Siegel, and A. G. Stefanopoulou, “Towards better estimability of electrode-specific state of health: Decoding the cell expansion,” J. Power Sources, vol. 427, pp. 101–111, July 2019. Figure 1
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Liu, Minghao, Jianxiang Wang, Qingxi Luo, Lingbo Sun, and Enming Wang. "Simulating Urban Expansion from the Perspective of Spatial Anisotropy and Expansion Neighborhood." ISPRS International Journal of Geo-Information 13, no. 3 (March 15, 2024): 91. http://dx.doi.org/10.3390/ijgi13030091.
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Exploring spatial anisotropy features and capturing spatial interactions during urban change simulation is of great significance to enhance the effectiveness of dynamic urban modeling and improve simulation accuracy. Addressing the inadequacies of current cellular automaton-based urban expansion models in exploring spatial anisotropy features, overlooking spatial interaction forces, and the ineffective expansion of cells due to traditional neighborhood computation methods, this study builds upon the machine learning-based urban expansion model. It introduces a spatial anisotropy index into the comprehensive probability module and incorporates a gravity-guided expansion neighborhood operator into the iterative module. Consequently, the RF-CNN-SAI-CA model is developed. Focusing on the 21 districts of the main urban area in Chongqing, the study conducts comparative analysis and ablation experiments using different models to simulate the land use changes between 2010 and 2020. Different model comparison results show that the recommended model in this study has a Kappa value of 0.8561 and an FOM value of 0.4596. Compared with the RF-CA model and the FA-MLP-CA model, the Kappa values are higher by 0.0407 and 0.1577, respectively, while the FOM values are improved by 0.0529 and 0.0654, respectively. Ablation experiment results indicate that removing gravity, SAI, and expansion neighborhood operators leads to a decrease in both Kappa and FOM values. These findings demonstrate that the RF-CNN-SAI-CA model, based on the expanded neighborhood iteration algorithm, effectively integrates spatial anisotropy features, captures spatial interaction forces, and resolves neighborhood cell failure issues, thereby significantly improving simulation effectiveness.
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., Marhaini, Eka Sri Yusmartini, and Kurnia Aini. "The Effect of Tricalcium Silicate (C3S) Percentage in Clinkerson the Cement Quality." International Journal of Engineering & Technology 10, no. 1 (January 13, 2021): 23. http://dx.doi.org/10.14419/ijet.v10i1.31294.
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Composite cement products produced by national cement factories in Indonesia should follow the required quality standards. The quality standard of composite cement refers to the SNI 7064:2014. Some physical parameters of the quality standards set are mortar compressive strength and autoclave expansion. Compressive strength is influenced by C3S and C2S in the clinker. The reaction of the formation of mineralogical compounds occurs when clinkers formed. Whereas the expansion by autoclave is influenced by the levels of free lime in the cement. This research was conducted to determine the effect of the percentage of tricalcium silicate (C3S) on the quality of cement with free lime <2% and free lime > 2% with variations of C3S in clinkers, namely 55%, 57%, 59%, 61%, 63%, 65%, and 67%. Physical parameters tested in this study are compressive strength of mortar, blaine, and autoclave expansion. While the chemical parameters tested in this study are free lime in cement and SO3. Based on the research, it was found that if the same percentage of C3S quality of cement having FCaO <2%, the initial compressive strength results were greater than FCaO> 2%, the ideal condition of the development of compressive strength for FcaO > 2%, 3 to 7 days was at the percentage of C3S clinker of 63,48%. Whereas the development of ideal compressive strength for 7 to 28 days is at the clinker C3S percentage of 64,85%. For FCaO <2% the ideal condition 3 days to 7 days is at the percentage of clinker C3S of 62,79% and the development of compressive strength 7 to 28 days is at the percentage of clinker C3S of 54.77%. The expansion with autoclave experiencing expansion that does not meet the minimum requirements of SNI 7064:2014 are samples with a percentage of C3S 54,86% and 61% with FCaO > 2%.
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Park, Han‐Eol, Dongkil Choi, Ji Su Park, Changgon Sim, Sohyun Park, Sunah Kang, Hyunsoo Yim, et al. "Tissue Expansion: Scalable and Isotropic Expansion of Tissues with Simply Tunable Expansion Ratio (Adv. Sci. 22/2019)." Advanced Science 6, no. 22 (November 2019): 1970131. http://dx.doi.org/10.1002/advs.201970131.
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Breen, R. "Educational Expansion and Social Mobility in the 20th Century." Social Forces 89, no. 2 (December 1, 2010): 365–88. http://dx.doi.org/10.1353/sof.2010.0076.
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Tenenbaum, David J. "Land Use. The Slippery Slope of Ski Expansion." Environmental Health Perspectives 109, no. 3 (March 2001): A112. http://dx.doi.org/10.2307/3434674.
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Canady, Valerie A. "Uninsured with SMI denied care without Medicaid expansion." Mental Health Weekly 25, no. 14 (April 6, 2015): 3–5. http://dx.doi.org/10.1002/mhw.30139.
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Möllerová, J. "Notes on invasive and expansive trees and shrubs." Journal of Forest Science 51, Special Issue (May 17, 2019): 19–23. http://dx.doi.org/10.17221/11844-jfs.
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Expansion and invasion of plants indicate successful colonization and competitive abilities of species. There are fewer invasive and expansive woody plants than herbs. Main expansive (native species) trees and shrubs are Acer platanoides, Acer pseudoplatanus, Clematis vitalba, Crataegus sp. div., Fraxinus excelsior, Prunus spinosa, Rubus sp. div., Sambucus nigra. Main invasive (alien species) are Acer negundo, Ailanthus altissima, Amorpha fruticosa, Cytisus scoparius, Fraxinus pennsylvanica, Lycium barbarum, Mahonia aquifolium, Physocarpus opulifolius, Pinus strobus, Populus × canadensis, Prunus serotina, Quercus rubra, Rhus typhina, Robinia pseudoacacia, Symphoricarpos albus, Syringa vulgaris. Dominant characteristics of expansive and invasive species are dispersibility of seeds and capacity of vegetative propagation.
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Anand, Ketan, Markus Andreas Schubert, Agnieszka Anna Corley-Wiciak, Davide Spirito, Cedric Corley-Wiciak, Wolfgang Matthias Klesse, Andreas Mai, Bernd Tillack, and Yuji Yamamoto. "(G03 - Best Student Presentation Award) Lateral Selective SiGe Growth for Dislocation-Free Virtual Substrate Fabrication." ECS Meeting Abstracts MA2022-02, no. 32 (October 9, 2022): 1218. http://dx.doi.org/10.1149/ma2022-02321218mtgabs.
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SiGe virtual substrates (VS) having low-surface roughness with less defects are essential for fabricating emerging quantum devices such as qubits. Various techniques to grow VS are reported e.g. conventional graded buffers (1,2) and reverse graded buffers (3). However, these methods require several micrometer-thick buffer layers, having threading dislocations (TDs) network and develop crosshatch patterns resulting in high surface roughness, needing chemical mechanical polishing for planarization. In our previous work, lateral-selective Ge growth (4) was performed in a cavity formed by selective vapor phase etching (VPE) of Si from side of mesa-patterned SiO2 /Si structures fabricated on buried oxide (BOX) to create smooth and dislocation-free local Ge by horizontal aspect ratio trapping (ART). In this work, we demonstrate lateral-selective SiGe growth to realize smooth and dislocation-free local SiGe VS by lateral ART and discuss its surface morphology, strain and dislocations. Lateral-selective SiGe growth is done in a reduced-pressure chemical vapor deposition (RPCVD) system. Thermally oxidized silicon-on-insulator (SOI) wafers with 300 nm SiO2/300 nm Si/2 μm BOX are used. For the sample preparation, 6.3 μm square checkerboard SiO2/Si mesa structure with [110] oriented sidewalls is fabricated by photolithography patterning and reactive ion etching. After standard RCA cleaning followed by HF dip, the wafer is loaded into RPCVD reactor and pre-baked at 850oC in H2 to remove residual oxide. Thereafter, lateral HCl VPE of Si is performed at 850oC from side of mesa. Si pillar remains at center of the mesa. Then, SiGe is selectively deposited in the cavity around the Si pillar using a SiH2Cl2-GeH4-HCl gas mixture at 750oC. Finally, the top SiO2 is removed by HF. Atomic force microscopy (AFM) is used to measure the surface roughness. Energy dispersive X-Ray spectroscopy (EDX) is used for measuring Ge content distribution in SiGe. Micro-Raman spectroscopy is used to analyze strain distribution in Si and SiGe. Nano-beam diffraction (NBD) is employed for estimating the relative change of in- and out-of-plane SiGe lattice parameters. Plan-view transmission electron microscopy (TEM) is used for imaging dislocations. Fig. 1 shows the AFM image for surface morphology of lateral-selective Si0.6Ge0.4 around the Si pillar. SiGe has root mean square roughness of ~0.16 nm, which is similar to blanket Si(001) (~0.14 nm), because the SiGe surface roughness is determined by interface roughness of top SiO2 and sacrificially etched Si. Uniform Ge content of ~40% in SiGe layer is observed by EDX analysis (Fig. 2). In the Si pillar part of Fig. 3, relative uniform tensile-strain of ~0.4% is observed. Since Si is negligibly strained in unpatterned area of SOI (taken as reference), hence during HCl VPE at 850oC, Si pillar/SiO2 interface could slip by higher thermal expansion of Si as interface decreases. Tensile-strain in Si pillar could be formed during cooling process. Ideally, ~1.68% lattice mismatch strain should exist in fully-relaxed ~40% SiGe on Si. However, higher tensile-strain (~2.5%) in SiGe is observed at corners along [010]. To clarify the reason of higher strain at corners, in- and out-of-plane SiGe lattice parameters near Si pillar (as marked in Fig 4(a)) are investigated by NBD. Higher in-plane lattice parameter in [110] is observed in the edge part of the SiGe lamella as compared to the center part (Fig. 4(b)). However, out-of-plane lattice parameter in [001] is homogeneous across entire SiGe (Fig. 4(c)). Because SiGe has uniform Ge concentration as shown in Fig. 2, higher lattice parameter in the edge part of Fig. 4(b) is caused by strain difference. This is because SiGe lamella edge (away from Si pillar) is more relaxed as compared to SiGe lamella center (beside Si pillar) which is confirmed by vertically grown ~700 nm 40% SiGe on blanket Si(110). Symmetric strain distribution does also exist in 90° rotated direction. Therefore, the tensile-strain in [010] is induced from both [110] and [-110]. In Fig. 5, stacking faults of SiGe on (111) plane are observed along [110] and [1-10]. TDs are present along [111], terminated by top SiO2/BOX and located up to first ~400 nm from Si while misfit dislocations are at Si/SiGe interface. Wide dislocation-free area in SiGe is present along [010]. This technique enables dislocation-free local SiGe-on-insulator substrate fabrication which can be applied for thin and high quality VS for the quantum devices. References E. A. Fitzgerald et al., J. Appl. Phys., 63, 693 (1988). E. A. Fitzgerald et al., Appl. Phys. Lett., 59, 811 (1991). V. A. Shah et al., Appl. Phys. Lett., 93, 192103 (2008). Y. Yamamoto et al., ECS J. of Solid State Sci. and Technol., 3, 353 (2014). Figure 1
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Dr. Naveen Prasadula, Dr Naveen Prasadula. "A Study on Profitable of Futures with the Reference to SBI Bank." International Journal of Information Technology and Management 17, no. 1 (September 3, 2024): 1–6. http://dx.doi.org/10.29070/mqdy3790.
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New instruments and reengineering of the financial system were introduced in India in 1992 as apart of economic market reforms. One among them was that the growth and innovation were slow infamiliarizing Securities. The formation and expansion of derivatives in Indian markets are moderately alatest spectacle. Subsequently its commencement in June 2000, the products need devises displayedepidemicaugmentation in magnitude and the number of bartered conventional agreements. Significanttermend product guides an expansive class of financial tools that specifically possess options andfutures. These mechanisms emanate their significance from the underlying asset's price and otherrelated variables. They accomplish not having a value of their own and originate their importance fromthe prerogative they give to their proprietors to own some additional financial support or safety. Thepresent study is deliberate in examining the financial results obeying SBI Bank Ltd.
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Schofer, E. "Cross-national Differences in the Expansion of Science, 1970-1990." Social Forces 83, no. 1 (September 1, 2004): 215–48. http://dx.doi.org/10.1353/sof.2004.0125.
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Habibi, M. R., M. Rashidinejad, and A. Abdollahi. "A new adequacy evaluation method for transmission expansion planning problems." Scientia Iranica 23, no. 3 (July 1, 2016): 1310–17. http://dx.doi.org/10.24200/sci.2016.3899.
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Hope, Kristin. "Enforcing Post-Transcriptional Circuitries to Achieve Human Hematopoietic Stem Cell Expansion." Blood 130, Suppl_1 (December 7, 2017): SCI—46—SCI—46. http://dx.doi.org/10.1182/blood.v130.suppl_1.sci-46.sci-46.
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Abstract The balance between hematopoietic stem cell (HSC) differentiation and self-renewal is central to clinical regenerative paradigms. Unravelling the precise molecular mechanisms that govern HSC fate choices will thus have far reaching consequences for the development of effective therapies for hematopoietic and immunological disorders. There is an emerging recognition that beyond transcription, HSC homeostasis is subject to post-transcriptional control by RNA-binding proteins (RBPs) that ensure precise control of gene expression by modulating mRNA splicing, polyadenylation, localization, degradation or translation. RBPs can synchronously regulate the fates of operationally similar RNAs, in what have been termed RNA regulons. We have used a variety of functional approaches, in combination with unbiased genome- and proteome-scale, methods to define the tenets that govern this regulation and to determine key downstream circuitries of stem cell-regulating RBPs whose targeting could provide the basis for novel regenerative treatments. Through loss-of-function efforts, we have identified the RBP, MSI2, as a required factor for human HSC maintenance. By contrast, at supraphysiological levels, MSI2 has a profound positive effect on human HSC self-renewal decisions. Using a combination of global profiling, including mapping MSI2's targets through cross-linking immunoprecipitation (CLIP)-seq, we show that MSI2 achieves its ex vivo self-renewal-promoting effects by directing a co-ordinated post-transcriptional repression of key targets within the aryl hydrocarbon receptor (AHR) pathway. We are currently exploring the "rules" by which MSI2 influences its downstream effects on target RNAs and how it functions, in combination with other protein interactors, to instill a putative RBP regulatory code in HSCs. HSCs exhibit highly unique epigenomes, transcriptomes and proteomes and it is this distinctive molecular landscape that provides the canvas upon which MSI2, and indeed any other HSC-specific RBP exert their post-transcriptional influence over stem cell function. As such, to decipher the bona fide RNA networks that RBPs function upon in HSCs and to understand how they influence this network to enforce self-renewal, we are working towards performing systematic studies of RBP regulons in these cells specifically. In turn these approaches are elucidating a host of RBPs and post-transcriptional control mechanisms previously unappreciated for their role in HSC control. When modulated appropriately, we can successfully tailor these post-transcriptional regulons to enforce desired HSC outputs ex vivo. In summary, approaches to elucidate key HSC-regulatory RBPs and their protein and RNA interactomes provide valuable insights into a layer of HSC control previously not well understood, and one that can be capitalized on to achieve successful HSC expansion. Disclosures No relevant conflicts of interest to declare.
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Ramsay, Robert G., and Helen E. Abud. "Exploiting induced senescence in intestinal organoids to drive enteroendocrine cell expansion." Stem Cell Investigation 4 (May 9, 2017): 36. http://dx.doi.org/10.21037/sci.2017.04.06.
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Agarwal, Rajiv. "What are the Consequences of Volume Expansion in Chronic Dialysis Patients?" Seminars in Dialysis 28, no. 3 (February 9, 2015): 231–32. http://dx.doi.org/10.1111/sdi.12349.
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Davies, Simon J. "What are the Consequences of Volume Expansion in Chronic Dialysis Patients?" Seminars in Dialysis 28, no. 3 (February 9, 2015): 239–42. http://dx.doi.org/10.1111/sdi.12350.
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Elsayed, Mohamed E., and Austin G. Stack. "What are the Consequences of Volume Expansion in Chronic Dialysis Patients?" Seminars in Dialysis 28, no. 3 (February 9, 2015): 235–39. http://dx.doi.org/10.1111/sdi.12351.
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Gajanayaka, Ranil, and Steven Coca. "What are the Consequences of Volume Expansion in Chronic Dialysis Patients?" Seminars in Dialysis 28, no. 3 (February 9, 2015): 247–49. http://dx.doi.org/10.1111/sdi.12352.
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Hecking, Manfred, Hugh Rayner, and Peter Wabel. "What are the Consequences of Volume Expansion in Chronic Dialysis Patients?" Seminars in Dialysis 28, no. 3 (March 1, 2015): 242–47. http://dx.doi.org/10.1111/sdi.12355.
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Schiller, Brigitte, Rohini Arramreddy, and Wael Hussein. "What are the Consequences of Volume Expansion in Chronic Dialysis Patients?" Seminars in Dialysis 28, no. 3 (March 1, 2015): 233–35. http://dx.doi.org/10.1111/sdi.12356.
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Mahutga, Matthew C. "Theoretical Holism in the Sociology of Development." Sociology of Development 2, no. 1 (2016): 1–24. http://dx.doi.org/10.1525/sod.2016.2.1.1.
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In this article, I apply Alderson and Nielsen's (1999) holistic approach to the sociology of development by revisiting the consequences of private markets and foreign direct investment (FDI) for earnings inequality during postsocialist transition. I begin by arguing that FDI increases the pace of private market expansion and thereby affects inequality through an indirect causal pathway unrecognized in the literature. The total effect of FDI thus depends in part on how private markets drive distributional change. I then introduce a maturation thesis to reconcile debates over the distributional consequences of private markets, where private markets first reduce and then increase inequality. If FDI increases the pace of private market expansion and if the distributional consequences of private markets increase as they expand, then FDI's total effect on inequality should grow with the expansion of private markets. Evidence drawn from a time-series crosssection regression analysis of earnings inequality among 18 transition countries supports this intervention. FDI increases the pace of private market expansion, and the effect of private markets changes from negative to positive as private markets expand. Thus the total effect of FDI increases with the size of the private market. I conclude by implicating these findings in debates about postsocialist transition and the sociology of development more generally.
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Larsson, Jonas. "RNAi Screens for Maintenance of Hematopoietic Stem Cell Phenotype During Culture." Blood 130, Suppl_1 (December 7, 2017): SCI—45—SCI—45. http://dx.doi.org/10.1182/blood.v130.suppl_1.sci-45.sci-45.
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Successful ex vivo expansion of hematopoietic stem cells (HSCs) could greatly enhance cell- and gene therapy applications in treatment of malignant and inherited hematological disorders. It has therefore been a long-standing goal in the field to gain a better understanding of the genes and pathways that regulate the self-renewal ability of HSCs. We have developed RNAi screening strategies to identify modifiers of self-renewal/proliferation in human hematopoietic stem- and progenitor cells (HSCPs). Employing pooled lentiviral shRNA libraries targeted to human cord blood derived CD34+ cells, we use the limited persistence of HSPCs under ex vivo culture conditions as a basis for functional selection of shRNAs conferring prolonged maintenance or expansion of undifferentiated cells. From the screens we have been able to identify directly targetable genes such as p38 MAPK, which can be pharmacologically inhibited to enhance the stem cell output of cultured cord blood cells. Additionally, we have found several epigenetic regulators among the top-scoring genes, including genes of the cohesin family, which modulate chromatin architecture, and JARID2, an important modifier of polycomb repressive complex 2 (PRC2). Depletion of either the cohesin genes or JARID2 by shRNA impairs differentiation and enhances both in vitro expansion and the in vivo reconstitution capacity of human HSPCs. However, whether these genes can be targeted pharmacologically to support HSC expansion remains to be explored. The screens have further identified a number of shRNAs that display a remarkable ability to expand HSPCs in culture, but whose gene targets have not been validated, indicating that they are affecting one or more genes in a non-specific manner. We performed gene expression profiling of cells transduced with these off-target shRNAs to gain insight about the molecular context under which HSPCs are propagated ex vivo. A common expression signature was the down-modulation of cellular stress response genes, such as p38 MAPK (previously identified in the screens) as well as genes involved in NF-□B signaling. Indeed, we found that pharmacological inhibition of NF-□B signaling leads to a significant improvement of stem cell function, from ex vivo cultured cord blood derived CD34+ cells, as assessed by transplantation to NSG mice. The effect of NF-□B inhibition was most critical early during the culture where it reduced the levels of several inflammatory and stress-related cytokines that are induced as an immediate response to culture initiation. Taken together, findings from our RNAi screens indicate that ex vivo HSC expansion is facilitated by targeting two distinct gene categories: cellular stress response genes activated by the culture conditions, as well as epigenetic regulators controlling the balance between renewal and differentiation. In order to define the most optimal expansion conditions we are currently assessing the combined targeting of several of these factors in conjunction with other compounds such as SR1 and UM171 using cellular barcoding. Here, cells are genetically marked by lentivirally delivered barcode sequences prior to expansion culture, which enables a precise detection and comparison of the stem cell output from multiple different expansion conditions in a directly competitive manner within a single xenografted animal. Disclosures No relevant conflicts of interest to declare.
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Banos, Vincent. "Le patrimoine au risque de son expansion : vers une « naturalisation » des territoires ?" Sud-Ouest européen, no. 30 (December 1, 2010): 37–51. http://dx.doi.org/10.4000/soe.1234.
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Witman, Nevin, and Makoto Sahara. "Expansion of cardiac progenitors from reprogrammed fibroblasts as potential novel cardiovascular therapy." Stem Cell Investigation 3 (August 5, 2016): 34. http://dx.doi.org/10.21037/sci.2016.07.06.
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